Viaduct wind tunnel model and test method

Abstract

The invention relates to a viaduct wind tunnel model and a test method, and relates to the technical field of wind tunnel tests. The viaduct wind tunnel model comprises a test platform and at least two model units which are arranged on the test platform and are mutually inserted. Each model unit comprises a telescopic supporting stand column and a bridge deck structure arranged on the top of the telescopic supporting stand column, and the bridge deck structure comprises a beam body and a bridge deck arranged on the beam body. The bridge deck comprises a lower plate body fixedly arranged on the beam body, a height adjusting device arranged on the lower plate body, an upper plate body arranged on the height adjusting device and a side plate arranged between the upper plate body and the lower plate body, the beam body is in sliding connection with the supporting stand columns, and the supporting stand columns can be movably adjusted in the bridge direction; key parameters such as the bridge clearance height, the clear span and the bridge floor structure thickness can be flexibly adjusted through one model, and the model is suitable for wind tunnel tests of viaducts with different parameters, so that proper bridge parameters are screened to reduce sand damage to the maximum extent.

Description

Technical Field

[0001] This invention belongs to the field of wind tunnel testing technology, and specifically relates to a wind tunnel model and testing method for an elevated bridge. Background Technology

[0002] Elevated bridges, as an engineering form that relies on high-support structures to cross terrain obstacles, are a commonly used road construction method in the complex geomorphological units of the Northwest Sandy Region, replacing traditional embankment roadbeds. By raising the track elevation, they reduce wind and sand disturbance to the substructure, thus mitigating the risk of sand damage. However, the bridge structure itself significantly alters the near-surface wind field characteristics, leading to complex changes in flow field parameters such as wind speed and turbulence intensity in the area under the bridge and near the piers. These changes in the flow field directly affect the transport and deposition patterns of sand, often resulting in sand accumulation under the bridge and on the leeward side of the piers. In severe cases, this can bury the piers, block the bridge openings, and threaten the structural stability of the bridge and the traffic capacity of the roads beneath it. To scientifically assess the impact of the wind and sand environment on bridges and optimize design parameters (bridge clearance height, clear span, and bridge deck thickness), wind tunnel testing is a crucial research method. By simulating the actual wind and sand environment in a wind tunnel using a scaled-down model, the flow field characteristics and sand accumulation morphology and intensity under different bridge design parameters can be quantitatively analyzed, thereby selecting the bridge parameter design scheme that can minimize sand damage.

[0003] However, existing wind tunnel model testing techniques for viaducts have significant limitations. Traditional models are mostly designed with fixed parameters and customized for specific bridge designs. When it is necessary to study the impact of different clearance heights, spans, or deck thicknesses on aeolian environments, multiple physical models of different sizes are usually required. This approach is not only costly but also time-consuming and inefficient. More importantly, subtle differences between different models can reduce the comparability of test results, making it difficult to accurately analyze the impact of changes in a single parameter. Therefore, there is an urgent need to develop a flexible and adjustable wind tunnel testing model and method for viaducts, capable of conveniently and accurately adjusting key geometric parameters such as bridge clearance height, span, and deck thickness without changing the main model. This will greatly improve wind tunnel testing efficiency, reduce costs, and ensure the consistency and comparability of parameter studies, providing more reliable and efficient experimental support for the wind-resistant and sand-proof optimization design of viaducts in desert areas. Summary of the Invention

[0004] To address the aforementioned issues, this invention provides a wind tunnel model and testing method for elevated bridges. A single model allows for adjustments to parameters such as bridge clearance height, net span, and bridge deck thickness to accommodate elevated bridge tests with varying parameters.

[0005] To achieve the above objectives, the present invention provides the following solution: A wind tunnel model for an elevated bridge includes a test platform and at least two model units interlocked on the test platform. Each model unit includes a retractable support column and a bridge deck structure mounted on top of the retractable support column. The bridge deck structure includes a beam and a bridge deck panel mounted on the beam. The bridge deck panel includes a lower plate fixed to the beam, a height adjustment device mounted on the lower plate, an upper plate mounted on the height adjustment device, and a side plate between the upper plate and the lower plate. The beam is slidably connected to the retractable support column, and the retractable support column is adjustable and movable along the longitudinal direction of the bridge.

[0006] Preferably, sealing gaskets are provided on the mating surfaces of the telescopic section of the telescopic support column and the lower plate, as well as on the mating surfaces of the upper plate and the lower plate.

[0007] Preferably, the retractable support column includes a hollow fixed support column, a sliding support column sleeved inside the fixed support column, and a lifting mechanism disposed between the bottom surface of the fixed support column and the bottom surface of the sliding support column.

[0008] Preferably, the height adjustment devices are arranged in a quincunx pattern, and the distance between adjacent height adjustment devices is 2 to 3 meters.

[0009] Preferably, the lifting mechanism and the height adjustment device are one of an electric push rod, a hydraulic push rod, or a pneumatic push rod.

[0010] Preferably, both the test platform and the bottom surface of the beam are provided with slide rails for the retractable support column to slide along the bridge direction, and the slide rails are provided with fixing components for fixing the retractable support column.

[0011] Preferably, a horizontal scale is provided on the test platform along the longitudinal direction of the bridge and on one side of the slide rail, and a vertical scale is provided on the test platform on one side of the bridge deck structure.

[0012] Preferably, the test platform has a cavity for accommodating the retractable support column, and the cavity is filled with sealing filler for filling the gap between the cavity and the retractable support column.

[0013] Preferably, the bridge deck structure is provided with railway tracks.

[0014] This invention also discloses a wind tunnel testing method for elevated bridges, which utilizes the aforementioned wind tunnel model for elevated bridges. The method is characterized by the following main steps: The retractable support column is placed on the test platform, and at least two model units are plugged together to form an elevated bridge model. The height of the retractable support columns, the spacing between the retractable support columns, and the thickness of the bridge deck structure can be adjusted by setting the bridge clearance height, clear span, and bridge deck structure thickness. Conduct wind tunnel tests, obtain relevant data, and analyze the data.

[0015] The present invention achieves the following technical effects compared to the prior art: By setting up retractable support columns that slide along the beam, and by installing a height adjustment device between the upper and lower plates, the height of the retractable support columns, the spacing between adjacent retractable support columns, and the thickness of the bridge deck structure can be adjusted. This allows for targeted adjustments to the bridge's clearance height, clear span, and bridge deck structure thickness. A single model can simulate different viaduct structures, thus improving the model's applicability. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Appendix Figure 1 This is a schematic diagram of the overall structure of the wind tunnel model of the viaduct disclosed in the embodiment of the present invention; Appendix Figure 2 This is a schematic diagram of the elevated bridge wind tunnel model disclosed in the embodiments of the present invention when the bridge deck structure is not set; Appendix Figure 3 This is a schematic cross-sectional view of the wind tunnel model of the viaduct disclosed in the embodiment of the present invention; The components include: 1. Bridge deck structure; 2. Telescopic support columns; 3. Upper plate; 4. Lower plate; 5. Test platform; 6. Horizontal scale; 7. Height adjustment device; 8. Sealing filler; 9. Sealing gasket. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] The purpose of this invention is to provide a wind tunnel model for elevated bridges, which allows for the adjustment of parameters such as bridge clearance height, clear span, and bridge deck thickness through a single model, making it suitable for elevated bridge tests with different parameters.

[0020] refer to Figures 1-3 This invention discloses a wind tunnel model and testing method for an elevated bridge, comprising at least a test platform 5. At least two interlocking model units are mounted on the test platform 5, and adjacent model units are interlocked to form an elevated bridge model. Each model unit includes a retractable support column 2. A bridge deck structure 1 for supporting loads is mounted on the top of the retractable support column 2. The bridge deck structure 1 includes a beam, and a bridge deck panel is mounted on the beam. The bridge deck panel includes a lower plate 4 mounted on the beam, a height adjustment device 7 mounted on the lower plate 4, and an upper plate 3 mounted on the height adjustment device 7. A side plate is positioned between the upper plate 3 and the lower plate 4. The upper plate 3, lower plate 4, and side plate together form a sealed structure. The beam and the retractable support column 2 are slidably connected. Next, the retractable support column 2 can be moved and adjusted along the bridge direction. By setting the retractable support column 2, the retractable support column 2 slides along the beam body, and a height adjustment device 7 is set between the upper plate 3 and the lower plate 4. The height of the retractable support column 2, the spacing between adjacent retractable support columns 2, and the thickness of the bridge deck structure 1 can be adjusted. In this way, the bridge clearance height, clear span, and bridge deck structure 1 thickness can be adjusted in a targeted manner. Key parameters such as bridge clearance height, clear span, and bridge deck structure 1 thickness can be flexibly adjusted through a single model. This is suitable for wind tunnel tests of viaducts with different parameters, used to analyze the changes in their flow field and assess the sand accumulation near the bridge, thereby selecting appropriate bridge parameters to minimize sand damage.

[0021] refer to Figures 1-2 As one implementation method, sealing gaskets 9 are provided on the mating surfaces of the telescopic support column 2 and the lower plate 4, the telescopic section of the telescopic support column 2, and the mating surfaces of the upper plate 3 and the lower plate 4. While allowing the telescopic support column 2 and the upper plate 3 to extend and retract freely, this effectively prevents debris (such as sand and rainwater) from entering the expansion joint, protects the lower expansion mechanism (such as supports and load-bearing beams) from damage and corrosion, and avoids the problem of wind passing through the expansion joint during wind tunnel testing, thus improving the accuracy of the test.

[0022] It should be noted that the sealing gasket 9 can be either rubber or silicone.

[0023] refer to Figure 1 In this embodiment, the retractable support column 2 includes a hollow fixed support column, inside which a sliding support column is sleeved. The bottom surfaces of the fixed support column and the sliding support column are provided with lifting mechanisms, which can realize the lifting and lowering of the sliding support column.

[0024] It should be noted that the retractable support column is one of the following shapes: cylindrical, elliptical, or rectangular.

[0025] refer to Figure 1 In this embodiment, the height adjustment devices 7 are arranged in a quincunx pattern, and the distance between adjacent height adjustment devices 7 is 2 to 3 meters. By setting multiple height adjustment devices 7 and arranging them in a quincunx pattern, the load-bearing strength of the upper plate 3 can be improved while the upper plate 3 is raised and lowered.

[0026] It should be noted that the height adjustment device 7 can also be arranged in a rectangular or polygonal structure, as long as it can support the load on the upper plate 3.

[0027] refer to Figure 1 In one implementation, the lifting mechanism and height adjustment device 7 are one of electric push rods, hydraulic push rods or pneumatic push rods, to achieve rapid response in height and thickness adjustment.

[0028] refer to Figure 1 and Figure 2 In one embodiment, the test platform 5 and the bottom surface of the beam are both provided with slide rails for the retractable support column 2 to slide along the bridge direction. The slide rails are provided with fixing parts for fixing the retractable support column 2. By setting the slide rails, the retractable support column 2 can be guided and the spacing of the retractable support column 2 can be easily adjusted.

[0029] It should be noted that the fastener can be a pin or bolt structure, as long as it can fix the slide rail to the telescopic support column 2.

[0030] refer to Figure 1 and Figure 2 In one embodiment, a horizontal scale 6 is provided on the test platform 5 along the direction of the bridge and on one side of the slide rail. The distance between adjacent retractable support columns 2 can be precisely adjusted by setting the horizontal scale 6. A vertical scale is provided on the test platform 5 on one side of the bridge deck structure 1. The bridge clearance height and the thickness of the bridge deck structure 1 can be precisely adjusted by setting the vertical scale.

[0031] refer to Figures 1-2 In one embodiment, the test platform 5 is provided with a cavity for accommodating the retractable support column 2. The cavity is provided with a sealing filler 8 for filling the gap between the cavity and the retractable support column 2. This can simulate the wind tunnel test of the retractable support column 2 under the condition of foundation constraint, making the test data more accurate.

[0032] It should be noted that when the test platform 5 has a receiving cavity, the slide rail is set inside the receiving cavity. The sealing filler 8 is made of rubber, silicone, polyurethane or other polymer materials with a specific hardness, which provides a certain resistance stiffness for the swing and rotation of the telescopic support column 2, simulating the constraint effect of real soil or foundation on the pier. The sealing filler 8 consumes energy when deforming, simulating the damping characteristics of the foundation, that is, the phenomenon that the structural vibration energy is absorbed by the soil. By changing the material, hardness and compactness of the filler, researchers can accurately "adjust" the stiffness and damping of the simulated foundation to match it with the actual geological survey data of the target bridge.

[0033] refer to Figures 1-2 As one implementation method, railway tracks are installed on the bridge deck structure 1.

[0034] This invention also discloses a wind tunnel testing method for elevated bridges, which uses the elevated bridge wind tunnel model described above and mainly includes the following steps: The retractable support column 2 is placed on the test platform 5, and at least two model units are plugged together to form an elevated bridge model. Based on the preset bridge clearance height, clear span and bridge deck structure 1 thickness, adjust the height of the retractable support column 2, the spacing between the retractable support columns 2 and the thickness of the bridge deck structure 1 according to the values ​​on the corresponding horizontal and vertical scales. Then fix the retractable support column 2 with fasteners to prevent the retractable support column 2 from moving. A sealing gasket 9 is provided on the mating surfaces of the fixed support column and the sliding support column, and a sealing gasket 9 is also provided on the mating surfaces of the upper plate 3 and the lower plate 4. The sealing filler 8 is filled into the cavity, and the height of the sealing filler 8 is flush with the test platform 5; Conduct wind tunnel tests, obtain relevant data, and analyze the data.

[0035] It should be noted that, for those skilled in the art, it is obvious that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A bridge model for a bridge wind tunnel, characterized in that The test platform comprises at least two model units which are mutually inserted on the test platform, the model unit comprises a telescopic support column, a bridge deck structure arranged on the top of the telescopic support column, the bridge deck structure comprises a beam body, a bridge deck plate arranged on the beam body, the bridge deck plate comprises a lower plate body fixedly arranged on the beam body, a height adjusting device arranged on the lower plate body, an upper plate body arranged on the height adjusting device, and a side plate arranged between the upper plate body and the lower plate body, the beam body is in sliding connection with the telescopic support column, and the telescopic support column can be adjusted along the bridge direction.

2. The bridge model according to claim 1, wherein The telescopic section of the telescopic support column is provided with a sealing gasket on the matching surface of the lower plate body, and the upper plate body is provided with a sealing gasket on the matching surface of the lower plate body.

3. The bridge model according to claim 1, wherein The telescopic support column comprises a hollow fixed support column, a sliding support column sleeved in the fixed support column, and a jacking mechanism arranged between the bottom surface of the fixed support column and the bottom surface of the sliding support column.

4. The bridge model according to claim 3, wherein The height adjusting devices are arranged in a plum blossom shape, and the spacing between adjacent height adjusting devices is 2-3 m.

5. The bridge model according to claim 4, wherein, The jacking mechanism and the height adjusting device are one of an electric push rod, a hydraulic push rod or a pneumatic push rod.

6. The bridge model according to claim 1, wherein The test platform and the bottom surface of the beam body are provided with sliding rails for the telescopic support column to slide along the bridge direction, and the sliding rails are provided with fixing members for fixing the telescopic support column.

7. The bridge model according to claim 6, wherein A horizontal scale is arranged on one side of the sliding rails along the bridge direction on the test platform, and a vertical scale is arranged on one side of the bridge deck structure on the test platform.

8. The bridge model according to claim 1, wherein An accommodating cavity for accommodating the telescopic support column is formed on the test platform, and the accommodating cavity is provided with a sealing filler for filling the gap between the accommodating cavity and the telescopic support column.

9. The bridge model according to claim 1, wherein The bridge deck structure is provided with rails.

10. A method of testing a bridge in a wind tunnel using a bridge wind tunnel model according to any one of claims 1 to 9, characterised in that, The method mainly comprises the following steps: Placing the telescopic support column on the test platform, and inserting the at least two model units to form a viaduct model; Adjusting the height of the telescopic support column, the spacing between the telescopic support columns and the thickness of the bridge deck structure according to the preset bridge clearance height, net span and bridge deck structure thickness; Performing a wind tunnel test to obtain relevant data and analyze the data.

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